Escherichia coli is a ubiquitous pathogen of man and animals causing a wide variety of diseases of clinical and economic importance. The greatest cause of mortality in the world is infant death and E. coli diarrheal disease in areas of poor sanitation is one of the most important causes. E. coli has been estimated to cause about 40% of all travelers diarrhea. E. coli is the most frequent cause of hospital-acquired infections and infections of debilitated and traumatized persons. Bacteremias and burn-wound infections are frequently due to E. coli. E. coli is the most frequent cause of urinary tract infections causing acute and chronic cystitis and pyelonephritis. It is clear that the development of methods to prevent E. coli disease would alleviate much human misery and stop huge economic losses.
Applicant has surveyed a large number of pathogenic strains of E. coli from a number of human diseases and established that the great majority of them possess pili belonging to a single immunologically related family named "E. coli Type 1" pili. In a co-pending application (BTX 3.0-005 U.S. Ser. No. 187,049 filed Sept. 15, 1980) which is incorporated herewith by reference, there is disclosed a general methodology of serological analysis. This methodology shows that members of the E. coli Type 1 pilus family can be ranked in a hierarchial order from most senior to most junior. Antisera to the most senior pilus type can cross-react to a large extent with all other members in the family. Therefore, provision of a vaccine consisting of a single type of purified E. coli type 1 pili would protect against the great majority of E. coli infections of humans, that is, infections caused by strains bearing pili in the Type 1 family especially those strains with pili junior to the pili in the vaccine. There also exist other immunologically related families of pili on Escherichia coli strains pathogenic for humans. These families are unrelated immunologically to Type 1 pili associated with mannose-sensitive hemagglutination of guinea pig erythocytes. These are known as NMS pili (associated with non-mannose-sensitive hemagglutination of human erythoracytes). Vaccines derived from NMS pili would also be useful in providing protection against the various E. coli infections.